1. At atmospheric pressure, a sample of Cl2 gas has a volume of 3.45 L at 51.0ºC. What volume, in liters, will the Cl2 gas occupy if the temperature is decreased to -55.0ºC?

2. At constant temperature, a sample of 3.75 L of N2 at 775 mmHg pressure is compressed until the
volume decreases to 3.15 L. What is the new pressure of N2 in units of atmospheres?

The chemical composition of soil varies with depth. an article in communications in soil science and plant analysis describes chemical analyses of soil taken from a farm in western australia. fifty specimens were each taken at depths 50 and 250 cm. at a depth of 50 cm, the average no3 concentration (in mg/l) was 88.5 with a standard deviation of 49.4. at a depth of 250 cm, the average concentration was 110.6 with a standard deviation of 51.5. find a 95% confidence interval for the difference in no3 concentrations at the two depths.